| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.nemo.compiler.frontend.spark.transform; |
| |
| import org.apache.nemo.common.ir.OutputCollector; |
| import org.apache.nemo.common.ir.vertex.transform.NoWatermarkEmitTransform; |
| |
| import java.io.*; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.UUID; |
| |
| /** |
| * Transform which saves elements to a local text file for Spark. |
| * |
| * @param <I> input type. |
| */ |
| public final class LocalTextFileTransform<I> extends NoWatermarkEmitTransform<I, String> { |
| private final String path; |
| private String fileName; |
| private List<I> elements; |
| |
| /** |
| * Constructor. |
| * |
| * @param path the path to write elements. |
| */ |
| public LocalTextFileTransform(final String path) { |
| this.path = path; |
| } |
| |
| @Override |
| public void prepare(final Context context, final OutputCollector<String> outputCollector) { |
| fileName = path + UUID.randomUUID().toString(); |
| this.elements = new ArrayList<>(); |
| } |
| |
| @Override |
| public void onData(final I element) { |
| elements.add(element); |
| } |
| |
| @Override |
| public void close() { |
| try ( |
| Writer writer = |
| new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName, false), "utf-8")) |
| ) { |
| for (final I element : elements) { |
| writer.write(element + "\n"); |
| } |
| writer.close(); |
| } catch (final IOException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| } |